Last month a team of paleontologists announced that it had found several fossilized dinosaur embryos that were 190 million years old - some 90 million years older than any dinosaur embryos found so far. Those kinds of numbers are always a little daunting. Ever since I was a boy in a public elementary school in Iowa, I've been learning to face the eons and eons that are embedded in the universe around us.

I know the numbers as they stand at present, and I know what they mean, in a roughly comparative way. The universe is perhaps 14 billion years old. Earth is some 4.5 billion years old. The oldest hominid fossils are between 6 million and 7 million years old. The oldest distinctly modern human fossils are about 160,000 years old.

The truth of these numbers has the same effect on me as watching the night sky in the high desert. It fills me with a sense of nonspecific immensity. I don't think I'm alone in this.

One of the most powerful limits to the human imagination is our inability to grasp, in a truly intuitive way, the depths of terrestrial and cosmological time. That inability is hardly surprising because our own lives are so very short in comparison. It's hard enough to come to terms with the brief scale of human history. But the difficulty of comprehending what time is on an evolutionary scale, I think, is a major impediment to understanding evolution.

How long does it take an electron to jump from one atom to another? According to a team of physicists in Germany and Spain, the answer is just 320 attoseconds. They came to this conclusion using X-ray pulses to watch an electron as it travelled from a sulphur atom to the surface of ruthenium metal. The process was one of the fastest ever studied (Nature 436 373).

Chemistry starts with the movement of electrons, a motion that takes place in a matter of attoseconds — a timescale almost too small to comprehend. An attosecond is one billionth of a billionth of a second, and there are more attoseconds in a minute than there have been minutes in the history of the universe.

With a flash of light to stimulate an electron and attosecond x-ray flashes to follow its activities, scientists could directly observe such phenomena as an atom becoming ionized, or the bonding of two or more atoms into molecules. Sound like a technology for the far-distant future? Not according to a pair of researchers at Lawrence Berkeley National Laboratory.

Alexander Zholents and William Fawley, physicists at Berkeley Lab's Center for Beam Physics in the Accelerator and Fusion Research Division, have an idea for creating intense bursts of x-rays in pulse lengths of about 100 attoseconds. If you picture Niels Bohr's classic 1913 model of a hydrogen atom, it takes about 100 attoseconds for the electron to orbit the proton.

The old adage "seeing is believing" hardly applies to nanoscience, which operates on a scale of atoms and molecules. So how do you make something so miniscule and abstract appear real to the ordinary eye?
Why not through art?

Ever wanted to wish upon a star? Well, you have 70,000 million million million to choose from. That's the total number of stars in the known universe, according to a study by Australian astronomers. It's also about 10 times as many stars as grains of sand on all the world's beaches and deserts.

The first ever picture of the Earth taken from the Red Planet has been obtained by the Mars Global Surveyor (MGS) spacecraft. This is our world as the Martians would see it.

Distant Earth is blue and beautiful against the deep darkness of space. The Moon is close by.
It is another reminder of our smallness against the vastness of the cosmos. A mote of dust suspended in a sunbeam, as Carl Sagan once put it.

A new limit on photon mass, less than 10^-51 grams or 7 x 10^-19 electron volts, has been established by an experiment in which light is aimed at a sensitive torsion balance; if light had mass, the rotating balance would
suffer an additional tiny torque. This represents a 20-fold improvement over previous limits on photon mass. Photon mass is expected to be zero by most physicists, but this is an assumption which must be checked experimentally. A nonzero mass would make trouble for special relativity, Maxwell's equations, and for Coulomb's inverse-square law for electrical attraction. The work was carried out by Jun Luo and his colleagues at

Amid a fast game in a vast venue, sports photography seeks to freeze motion and isolate small portions of space for special consideration. In the scientific world of the ultrafast and ultrasmall, stroboscopic effects are achieved with greatly attenuated laser pulses. The advent of laser light served up in femtosecond (or 10^-15 second) bursts has helped to elucidate the molecular world by freezing their vibrational and rotational motions. Scientists would of course like to instigate and monitor even shorter times and distances.

Probably one of the most amazing photographs ever made was taken during the Apollo 8 mission in December of 1968. This was the first manned flight to leave Earth's orbit, allowing someone to see the whole Earth from space for the first time. As Anders said in his book, A View from Space, "We'd come 240,000 miles to see the moon, and it was the Earth that was really worth looking at."
Photograph published in LIFE January 10, 1969

Great fleas have little fleas
upon their back to bite 'em.
And little fleas have lesser fleas,
and so ad infinitum.
- Augustus De Morgan